Briquetting roll and pocketed segments therefor

ABSTRACT

A briquetting roll in which a steel roll body is provided with a peripheral groove having a radially outwardly facing bottom wall which is made up of planar chordal segments and having side walls at the side edges of the bottom wall with one side wall being in the form of an annular segment of a cone concentric with the axis of the roll. Bodies of hard wear resistant material are mounted in the groove, one on each chordal section of the bottom wall of the groove and have the one side inclined to fit the inclined wall with the other side spaced from and diverging from the radial side wall. Wedge bars between the radial side wall and the opposed sides of the segments are utilized for clamping the segments in place in the roll.

United States Patent Armbrust et al.

BRIQUETTING ROLL AND POCKETED SEGMENTS THEREFOR Inventors: William D.Armbrust, Greensburg;

Dennis J. Shallenberger, Latrobe; Charles E. Hill, Whitney, all of Pa.

Assignee: Kennametal lnc., Latrobe, Pa.

Filed: Mar. 28, 1974 Appl. No.: 455,518

US. Cl. 425/237; 425/363; 425/470 Int. Cl. B29c 3/02 Field of Search425/237 References Cited UNlTED STATES PATENTS 8/l974 Woodward 425/237Primary Examiner-J. Howard Flint, Jr. Attorney, Agent, or Firm-Melvin A.Crosby [57] ABSTRACT A briquetting roll in which a steel roll body isprovided with a peripheral groove having a radially outwardly facingbottom wall which is made up of planar chordal segments and having sidewalls at the side edges of the bottom wall with one side wall being inthe form of an annular segment of a cone concentric with the axis of theroll. Bodies of hard wear resistant material are mounted in the groove,one on each chordal section of the bottom wall of the groove and havethe one side inclined to fit the inclined wall with the other sidespaced from and diverging from the radial side wall. Wedge bars betweenthe radial side wall and the opposed sides of the segments are utilizedfor clamping the segments in place in the roll.

12 Claims, 3 Drawing Figures as -+o 1 BRIQUETTING ROLL AND POCKETEDSEGMENTS THEREFOR The present invention relates to briquetting machinesand is particularly concerned with the construction of a briquettingroll and segments of hard wear resistant material for mounting in theperiphery of the roll and to the formation of the segments.

Briquetting devices are known and, in general, comprise a pair of rolls,or wheels, running on parallel axes with the peripheries in juxtaposedrelation at one peripheral point and with the rolls rotating inrespectively different directions. Material introduced between the rollson the downgoing sides of the rolls is captured by segments mounted onthe rolls and formed into briquettes in pockets which are formed in thesegments.

Many different arrangements have been provided for clamping the segmentsin such a roll and for forming the segments themselves but, heretofore,certain difficulties have presented themselves in respect of the cost ofmanufacture and the rigidity with which the segments are held in placeand the like.

With the foregoing in mind, the primary object of the present inventionis the provision of an improved briquetting roll and segment and segmentclamping arrangement therefor.

A still further object is the provision of a briquetting roll and havingsegments mounted on the periphery thereof which can be manufactured moreinexpensively than briquetting roll arrangements according to the priorart.

BRIEF SUMMARY OF THE INVENTION According to the present invention, thebriquetting roll consists of a steel wheel or roller adapted for beingmounted on a shaft to be rotated thereby. A radially outwardly openingannular groove is formed in the periphery of the roll with the grooveconsisting of a plurality of planar chordal sections of equal size inend to end relation and each perpendicular to a respective radius of theroll.

The groove when viewed in cross section has one side wall upstandingtherefrom in the radial direction, while the other side wall is in theform of an annular section of a cone which is coaxial with the axis ofthe roll. The cone is so disposed that the side wall of the groove whichpertains thereto converges in the radially outward direction with theradial side wall.

A pocketed segment formed of a hard wear resistant material such as acemented hard metal carbide, tungsten carbide, for example, is mountedon each chordal section of the bottom wall of the groove and has oneside configured to engage the conical side of the side wall while theother side of the respective segment is spaced from the radial side walland diverges therefrom in the radially outward direction. Each segmenthas a flat bottom wall resting on the respective chordal section whilethe outer side of each segment is concentric with the axis of the rolland is formed with one or more pockets or portions of pockets in whichthe material to be briquetted will be compacted.

Each segment is held in place by a respective wedge bar that is disposedbetween the radial side wall of the groove and the opposed side of therespective segment and which is fixed to the roll by screws extendingthrough the wedge bar and threaded into the roll. The provision of thewedge bar provides for positively clamping the segments in place on theroll while, simultaneously, each segment is held in lateral compressionthereby assisting in the development of the strength of the hardmaterial from which the segments are made.

These and other objects and advantages of the present invention willbecome more apparent upon reference to the following detailedspecification taken in connection with the accompanying drawings inwhich:

FIG. 1 is a side view partly broken away of a briquetting wheel or rollaccording to the present invention.

FIG. 2 is a section indicated on line II-II of FIG. 1. FIG. 3 is a planview of a typical segment for a briquetting wheel.

DETAILED DESCRIPTION OF THE INVENTION Referring to the drawings somewhatmore in detail, the briquetting wheel, or roll, shown in FIGS. 1 and 2comprises a steel body 10 which may have a central bore 12 ofsubstantial size with diametrally opposed key recesses 14 formed in body10 and communicating with bore 12. The bore might, for example, be about10% inches in diameter, while the overall diameter of the steel part ofthe roll might be, for example, l7% inches in diameter.

As will best be seen in FIG. 2, the roll has an annular groove 16 formedtherein and consisting of a bottom wall 18 and two side walls 20 and 22.As will be seen in FIG. 2, the steel body of the roll may be about 6inches long and the groove may be about 5 inches long.

The bottom wall 18 will be seen in FIG. 1 to be made up of a pluralityof planar chordal sections 24, all of equal length and eachperpendicular to a respective radius of body 10 and all disposed anequal radial distance outwardly from the axis of rotation of body 10.

At one side, wall 22 of the groove 16 is radial but may differ from theradial a substantial amount as will become apparent hereinafter.

A particularly important feature of the present invention is to be foundin respect of side wall 20 which is opposed to side wall 22. Side wall20 is in the form of an annular section of a cone which is coaxial withbody 10. The outline of the cone is indicated at 26 in FIG. 2, and itwill be seen to be a relatively wide angle cone with the cone sidesmaking an angle, designated 28, of about 7% degrees with a radius toroll body 10.

The important thing about the angularity of side wall 22 is that thisside wall converges with side wall 20 in the radially outward directionso that the segments to be carried by the roll will be positivelyclamped therein when the assembly is completed. It will be evident thatthe side wall 22 is advantageously radial because this represents thesimplest machining operation to carry out on that side wall. The otherside wall 20 can also be relatively simply formed by a turning operationwhile the planar chordal sections 24 making up the bottom wall 18 ofgroove 16 can be formed by milling.

Mounted on each of the aforementioned planar chordal sections 24 ofbottom wall 18 of groove 16 is a respective segment 30. Segments 30 havepockets or portions of pockets 32 formed in the outwardly facing sidethereof in which the material to be briquetted will be compacted whenthe machine is in operation. As will be seen in FIG. 1, the outwardlyfacing side of each segment is concentric with the axis of roll body 10while the inwardly facing side of each segment is planar and rests on arespective chordal section in face to face engagement therewith.

The segments. in order to obtain suitable wear life. are advantageouslyformed of a cemented hard metal carbide material, such as tungstencarbide, and proper support of members made of this material isimportant. The material is extremely abrasion resistant and strong incompression but is relatively weak in tension and is rather brittle.

Members made of this material can, thus, be frac tured relativelyreadily unless the members are firmly supported at all times. The wheelbody of the present invention provides such support because the flatchordal sections 24 engage the bottoms of the segments while on the sideedges 21 of the segments facing wall 22 the segments have acorresponding configuration and each is, thus, in face to faceengagement with a respective segment of side wall 20.

The opposite side edge 34 of each segment is inclined at an angle ofabout 7Vz to the radial direction of roll body and this side edge ofeach insert is axially spaced from the opposite side wall 22 of thegroove. Each end edge of the segments, said end edges being indicated at36 in FIG. 1, are radial to the roll body 10 and in abutment with theend edges of the next adjacent segments.

Disposed between side edges 34 of each segment and side wall 22 of theroll body is a wedge member 38 configured on one side for face to faceengagement with side wall 22 of the groove and on the other side forface to face engagement with the opposed side edge of the respectivesegment. Each wedge bar has screws 40 ex tending therethrough andthreaded into the roll body 10 so that each wedge bar can be pulled downfirmly into wedging engagement with the respective segment 30.

When the wedge bars are pulled up tight, all of the segments are pressedfirmly against side wall of the groove and against the respectivechordal section of the bottom wall of the groove while, furthermore,each segment is held me state of lateral compression thereby enhancingthe useful strength of the segments.

The wedge bars 38, similarly to the segments 30, have their ends radialto the roll body 10 and preferably in substantially end to endengagement when the wedge bars are pulled down into clamping position.

The roll assembly illustrated is only one of several sizes that can bemade and shows sixteen segments and wedge bars. This proves to be apractical arrangement for a briquetting roll of the size illustrated.

In operation, the roll illustrated runs together with another roll, afragment of which is indicated in dotdash outline at 42 in FIG. 1. Therolls are mounted on parallel axes and are keyed to the respectiveshafts with the shafts being geared together or synchronized in somesuitable manner so that the pockets on the respective rolls alwaysremain in the same condition of registration. The rolls turn in thedirection indicated by the arrows 44 in FIG. 1, and granulated materialsupplied to the bight of the rolls in FIG. 1 will be compacted in thepockets of the segments and will come out at the bottom in the form ofbriquettes.

An important feature that results from the novel arrangement accordingto the present invention in which the side wall 20 of the wheel and theopposed side edges 2] of the segments are in the form of an annularsegment of a cone is that these surfaces can be formed relatively simplyon the respective members while, at the same time, each segment isfixedly located in the proper position on the roll body because eachsegment rests on a respective flat chordal section of the bottom wall ofthe groove,

Any tendency for a segment to move peripherally on the roll, due to theforces exerted thereon during a briquetting operation, will be stronglyopposed by the change in relationship that such movement would causebetween the curved side edge 2! of the respective segment and the curvedside wall 20 of the groove which is engaged thereby.

It has been found that the simple expedient of curving wall 20 in thedescribed manner and curving the opposed side edges 21 of the segments30 for face to face engagement therewith provides for the strong holdingof the segments in place against peripheral shifting of the segments onthe roll body while, at the same time, this beneficial end result isobtained in a quite inexpensive manner,

FIG. 3 shows a segment 30 in a plan view with the inclined edge 34 atone side and the conical side edge 21 at the other side.

Modifications may be made within the scope of the appended claims.

What is claimed is:

1. In a briquetting device; a roll having an outwardly opening annulargroove formed in the periphery thereof, the bottom wall of said groovebeing in the form of planar chordal sections in end to end relation andeach perpendicular to a respective radius of the roll, said groove whenviewed in cross section having one side wall which forms an acute firstincluded angle with the bottom wall of said groove while the other sidewall forms a second included angle with said bottom wall which is largerthan said first included angle, said side walls converging in theradially outward direction, said one side wall of said groove is in theform of an annular segment of a cone.

2. A briquetting device according to claim 1 in which said other sidewall of said groove is radial and forms an included angle with saidbottom wall which is a right angle.

3. A briquetting device according to claim 1 which includes a segmenthaving a planar bottom wall resting on each chordal section andcoextensive therewith in the circumferential direction, one side of saidsegment being inclined at the same angle as said one side wall andengaging said one side wall, the other side of said segment forming anobtuse inclined angle with the bottom wall of the groove and divergingfrom said other side wall of said groove in the radially outwarddirection, a wedge bar having one side engaging said other side wall ofsaid groove and the other side engaging said other side of said segment,and means for exerting radially inwardly directed thrust on said wedgebar to lock said segment in said groove while holding said segment in astate of lateral compression, the outwardly facing wall of each saidsegment being curved and concentric with the axis of said roll.

4. A briquetting device according to claim 1 which includes a segmenthaving a planar bottom wall resting on each chordal section of saidgroove and coextensive therewith in the circumferential direction, theends of adjacent ones of said segments being planar and radial to theroll and interengaged, one side of each said segment being formed forface to face engagement with said one side wall of said groove and theother side of each segment being planar and forming an obtuse angle withthe respective chordal section of the bottom wall of said groove, awedge bar for each segment having one side formed for face to faceengagement with said other side of the segment and the other side formedfor face to face engagement with the other side wall of the a groove,and clamp means for urging each said wedge bar radially inwardly betweensaid other side of the respective segment and the said other side wallof the groove to clamp the respective segment to the roll whilemaintaining the respective segment in a state of lateral compression,the outwardly facing side of each segment being concentric with the axisof said roll.

5. A briquetting device according to claim 4 in which said clamp meanscomprises screws extending through said wedge bars and threaded intosaid roll.

6. A briquetting device according to claim 4 in which said wedge barswhen in clamping position are in end to end relation.

7. A briquetting device according to claim 3 in which said segmentscomprise radially outwardly opening pockets therein.

8. A briquetting device according to claim 4 in which said segmentscomprise radially outwardly opening pockets therein.

9. A briquetting device according to claim 3 in which said segments areformed of a hard cemented metal carbide.

10. A briquetting device according to claim 4 in which said segments areformed of a hard cemented metal carbide.

11. A briquetting device according to claim 9 in which said metalcarbide comprises tungsten carbide.

12. A briquetting device according to claim 10 in which said metalcarbide comprises tungsten carbide. l

1. In a briquetting device; a roll having an outwardly opening annulargroove formed in the periphery thereof, the bottom wall of said groovebeing in the form of planar chordal sections in end to end relation andeach perpendicular to a respective radius of the roll, said groove whenviewed in cross section having one side wall which forms an acute firstincluded angle with the bottom wall of said groove while the other sidewall forms a second included angle with said bottom wall which is largerthan said first included angle, said side walls converging in theradially outward direction, said one side wall of said groove is in theform of an annular segment of a cone.
 2. A briquetting device accordingto claim 1 in which said other side wall of said groove is radial andforms an included angle with said bottom wall which is a right angle. 3.A briquetting device according to claim 1 which includes a segmenthaving a planar bottom wall resting on each chordal section andcoextensive therewith in the circumferential direction, one side of saidsegment being inclined at the same angle as said one side wall andengaging said one side wall, the other side of said segment forming anobtuse inclined angle with the bottom wall of the groove and divergingfrom said other side wall of said groove in the radially outwarddirection, a wedge bar having one side engaging said other side wall ofsaid groove and the other side engaging said other side of said segment,and means for exerting radially inwardly directed thrust on said wedgebar to lock said segment in said groove while holding said segment in astate of lateral compression, the outwardly facing wall of each saidsegment being curved and concentric with the axis of said roll.
 4. Abriquetting device according to claim 1 which includes a segment havinga planar bottom wall resting on each chordal section of said groove andcoextensive therewith in the circumferential direction, the ends ofadjacent ones of said segments being planar and radial to the roll andinterengaged, one side of each said segment being formed for face toface engagement with said one side wall of said groove and the otherside of each segment being planar and forming an obtuse angle with therespective chordal section of the bottom wall of said groove, a wedgebar for each segment having one side formed for face to face engagementwith said other side of the segment and the other side formed for faceto face engagement with the other side wall of the groove, and clampmeans for urging each said wedge bar radially inwardly between saidother side of the respective segment and the said other side wall of thegroove to clamp the respective segment to the roll while maintaining therespective segment in a state of lateral compression, the outwardlyfacing side of each segment being concentric with the axis of said roll.5. A briquetting device according to claim 4 in which said clamp meanscomprises screws extending through said wedge bars and threaded intosaid roll.
 6. A briquetting device according to claim 4 in which saidwedge bars when in clamping position are in end to end relation.
 7. Abriquetting device according to claim 3 in which said segments compriseradially outwardly opening pockets therein.
 8. A briquetting deviceaccording to claim 4 in which said segments comprise radially outwardlyopening pockets therein.
 9. A briquetting device according to claim 3 inwhich said Segments are formed of a hard cemented metal carbide.
 10. Abriquetting device according to claim 4 in which said segments areformed of a hard cemented metal carbide.
 11. A briquetting deviceaccording to claim 9 in which said metal carbide comprises tungstencarbide.
 12. A briquetting device according to claim 10 in which saidmetal carbide comprises tungsten carbide.